This application is being filed concurrently with related U.S. patent applications: Ser. No. 09/350,742 entitled xe2x80x9cMethods and Apparatus for Issuing Updates to Multiple Management Entitiesxe2x80x9d; entitled Ser. No. 09/350,800 xe2x80x9cMethods and Apparatus for Performing Mass Operations on a Plurality of Managed Devices on a Networkxe2x80x9d; Ser. No. 09/350,739 entitled xe2x80x9cMethods and Apparatus for Managing Heterogeneous Storage Devicesxe2x80x9d; Ser. No. 09/350,945 entitled xe2x80x9cPlatform Neutral Data Storage Management Method and Apparatusxe2x80x9d; all of which are incorporated herein by reference.
The present invention relates generally to methods and apparatus for committing configuration changes to managed devices prior to the completion of the configuration change, and more particularly to a system in which configuration changes which require a long time to complete are committed and made durable prior to the completion of the long term event.
When performing configuration altering commands to a storage device or other device on a computer system or network, two completion models are common. The first is a short term completion model in which the storage system or device controller processes the configuration change and returns status to the requester in near real time (e.g., less than 2 to 3 seconds). In the short term completion model, the controller simply takes the request from the user, processes the request to completion, and then returns the status to the user. The time required to complete the configuration task is nearly imperceptible to the human instigator and the task running on the host computer or management station requesting the configuration change is short lived; thus, the probability of other tasks running on the host computer or management station consuming large resources or threads is very low. This model is the current state of the art.
The second model is a long term completion model in which the configuration change requires an extend time to complete; for example, a complete reformat or relayout of data on a storage system. When a host computer or management station issues these long term configuration change events, several problems arise. First, the user issuing the configuration change request expects to see progress updates of the long term event to avoid the uncertainty of a xe2x80x9chungxe2x80x9d system. Second, if the processing thread on the management station is left open during the processing of the long term event, significant system resources are consumed and wasted by the open processing thread. The problem becomes particularly severe in the production environment in which many tens or hundreds of these long lived requests are active at any one point.
Attempts have been made in the prior art to address this problem by using the xe2x80x9cIMMEDIATExe2x80x9d status as described by the SCSI standard. With this particular model, the device controller simply returns the request with a xe2x80x9cgoodxe2x80x9d status and then processes the request to completion. The problem with this approach is that it typically does not provide progress status to the user. More importantly, it does not provide a state indication of the permanence of the requested operation in the event the operation is interrupted before it has completed (e.g., reset, power loss, or the like). Thus, what is needed is a system and method which will turn a long term configuration change event into a short term change event by releasing the processing thread in the management station after the configuration change event has become durable in the device controller, but still report progress of the configuration change to the management station and the requesting user.
According to the invention, a system and method for managing device configuration changes. The system and method preferably comprises a management station which issues a configuration change request to a managed device and waits for a reply from the managed device. The managed device receives the configuration change request from the management station and processes the change request until the configuration request is durable on the managed device. The managed device then returns a status to the management station indicating that the configuration request is durable. The management station receives the status from the managed device and stops waiting for a reply. In the meantime, the managed device continues processing the configuration change request.
In accordance with one aspect of the present invention, the system and method further comprises that after the management station receives the status from the managed device and stops waiting for a reply, the management station perferably starts an event completion status object, which shows the completion status of the configuration change request being processed on the managed device.
In accordance with yet another aspect of the present invention, the system and method further comprises that while the managed device is continues to process the configuration change request, the managed device periodically sends completion progress messages to the management station. The management station receives the completion progress messages from the managed device and updates the event completion status object in accordance with the completion progress messages. Preferably, the managed device will continue to send completion progress messages to the management station and the management station will update the event completion status object until the configuration change request is completely processed. After the managed device completes processing the configuration change request, the managed device preferably sends a change request completed message to the management station. The management station receives the change request completed message and notifies the user that the configuration change request is finished processing.
A more complete understanding of the present invention may be derived by referring to the detailed description of the preferred embodiments and claims when considered in connection with the figures, wherein like referenced numbers refer to similar items throughout the figures.